Dry-type Transformer
Dry Type Power Transformer Manufacturer
Honway Power supplies dry type transformers designed for indoor power distribution, industrial facilities, commercial buildings and other applications where oil-free transformer solutions are preferred.
Our dry type transformers use air as the cooling medium and epoxy resin insulation technology for reliable electrical performance and simplified maintenance requirements. Customized transformer solutions are available according to project voltage, capacity and application requirements.
What Is a Dry Type Transformer, and Why Projects Choose One
A dry type transformer insulates and cools the windings with solid insulation and air instead of mineral oil. There is no oil to leak, no fire suppression pit to build, no containment bund to pour, and no periodic oil testing to schedule. That is the entire reason the product category exists: it trades a small premium in unit price for a large reduction in installation cost and ongoing liability wherever equipment sits close to people, IT hardware, or flammable materials.
This is also where buyers most often over- or under-spec a project. Oil-immersed transformers remain cheaper per kVA and are the default choice for outdoor substations and pole-mounted distribution. A dry type transformer earns its premium specifically indoors, at altitude, in humid or dusty environments, or anywhere fire code, insurance underwriting, or building class forces the decision. Confirm which situation applies to your project before requesting a quotation — it determines the insulation class and enclosure rating, not just the price.
Honway Dry Type Transformer Product Range
- 30kVA–6000kVA MV&HV Dry-Type Transformers (0.38kV/12kV) — Honway's widest-range platform, covering both light commercial and heavy industrial capacity on a single customizable design.
- 100kVA 11kV/0.4kV Dry Type Transformer, IEC Certified — sized for residential and small commercial distribution.
- 315kVA 22kV/0.4kV Dry Type Transformer — export-oriented, commonly specified for schools, hospitals, and shopping malls.
- 630kVA 33kV/0.4kV Dry Type Power Transformer — for municipal buildings and data center rooms.
- 1250kVA 33kV/0.4kV Dry Type Transformer — sized for industrial park and infrastructure loads.
- 2000kVA 33kV/0.4kV Dry Type Transformer — for large commercial and industrial sites needing higher single-unit capacity.
- 2500kVA 33kV/0.4kV Dry Type Transformer — Honway's largest standard dry type unit, for key power infrastructure projects.
Need a capacity or voltage combination not listed above? Every unit on this page started as a custom request — Contact Us with your specification.
Custom Dry Transformer Solutions
Standard catalog dimensions rarely match every project's cable entry, busbar orientation, or civil foundation exactly. Honway's engineering team reviews project drawings and electrical specifications before finalizing a design, and customization typically covers:
- Rated capacity and voltage ratio outside standard steps
- Vector group and tap range
- Cooling configuration (AN/AF) and enclosure/IP rating
- Terminal and busbar orientation to match existing switchgear
- Third-party test and certification documentation for specific export markets
Cast Resin Construction
Honway's standard dry type transformer range uses cast resin (epoxy vacuum-cast) insulation. The high-voltage and low-voltage windings are cast under vacuum in epoxy resin reinforced with glass fiber, which eliminates air voids, resists moisture absorption, and gives the winding mechanical strength to withstand short-circuit forces. This is the same construction principle used across the SCB-class cast resin transformers common in data center, hospital, and metro-rail specifications worldwide.
Two cooling configurations are available on the cast resin platform:
- AN (natural air / self-cooled) — no fans, lower noise, lower maintenance, suited to base-load duty
- AF (forced air) — fan-assisted cooling that raises the same core-and-coil unit's continuous rating by roughly 15–20%, useful where a site has headroom for a larger transformer but not the physical space
Buyers sometimes ask about VPI (vacuum pressure impregnated, open-wound) dry type transformers as an alternative. VPI trades some environmental protection for slightly better heat dissipation and easier field repair. Honway's engineering focus is cast resin because it's the better default for export projects facing humid transport, variable site conditions, and long service intervals — but if your project specifically requires an open-wound VPI design, raise it during technical review and our engineers can advise whether it's the right fit.
Standards, Insulation Class, and Enclosure Rating
A dry type transformer quotation lives or dies on four numbers. Get these into your RFQ and the quotation you receive back will actually be comparable to competing bids:
- Standard: Honway's dry type transformers are designed to IEC 60076-11, the international standard covering dry type power transformer insulation, temperature rise, and test methods. Export orders to specific markets can be built to align with ANSI/NEMA or the destination country's national adoption of IEC — confirm this at inquiry stage, not after the design is fixed.
- Insulation class: Class F (155°C) is standard for most commercial and light-industrial projects. Class H (180°C) is available where ambient temperature is high or the transformer runs close to nameplate rating continuously — common in industrial plants and some data center specs.
- Temperature rise: Specified in kelvin above ambient (typically 100K or 120K depending on insulation class and loading profile). This number, not the insulation class alone, determines how much continuous overload margin the unit actually has.
- Enclosure / IP rating: IP00 (open, panel-mounted inside switchgear) up to IP23 (protected against water spray, suited to semi-outdoor or wash-down areas) covers most projects. Tell us the installation environment and we'll recommend the enclosure rather than you guessing at an IP number.
Certification: Honway's manufacturing and quality system operates under ISO 9001, with CE and IEC compliance documentation available per project. If your project requires a specific third-party test report (partial discharge, short-circuit withstand, temperature rise type test), request it during technical review — it affects lead time and should be confirmed before, not after, order placement.
Dry Type Transformer Applications
- Commercial buildings and high-rises: compact footprint and no oil containment requirement let the transformer sit inside the electrical room rather than a dedicated outdoor yard — relevant where floor space is priced by the square meter.
- Hospitals and public facilities: low fire risk and no oil spill exposure near patient-occupied areas is typically a code requirement, not a preference.
- Data centers: N+1 power architectures put transformers in enclosed rooms with tight clearances; cast resin's compact build and AF cooling option fit this footprint. See our Sizing Grid-Connected Photovoltaic Power Transformers article if your data center project also includes on-site solar.
- Industrial plants: dust, humidity, and continuous loading push most industrial specs toward Class H insulation and AF cooling rather than the commercial-grade default.
- EV charging infrastructure and substations: charging hubs increasingly specify dry type units for the same fire-code reasons as commercial buildings, plus faster permitting where oil containment isn't part of the civil design. See Smart Charging Station Power Transformer Solution Trends for sizing considerations specific to EV charging loads.
Noise is a recurring, underdiscussed spec across all of the above. If your project is noise-sensitive (hospital, office building, residential-adjacent site), say so at inquiry stage — it affects the cooling configuration (AN over AF where possible) and may call for a sound enclosure.
How to Choose the Right Dry Type Transformer
Most quotation delays come from missing one of these five inputs, not from anything complicated. Confirm each before sending an RFQ:
- Capacity (kVA): Size to present load plus realistic expansion, not theoretical maximum — oversizing increases no-load losses you pay for over the transformer's entire service life; undersizing forces early replacement.
- Voltage ratio: Primary voltage (matching the incoming network — commonly 10kV, 11kV, 20kV, 22kV, or 33kV in Honway's current range) and secondary voltage (usually 0.4kV), plus vector group if your project standard requires a specific one (Dyn11 is the common default for distribution duty).
- Environment: Indoor clean room vs. industrial floor vs. humid/coastal site determines insulation class and IP rating — this is the input buyers most often skip, and the one most likely to cause a mismatch after delivery.
- Standard and certification: Confirm IEC 60076-11 compliance is sufficient, or whether your project specification calls for a market-specific certification.
- Quantity and delivery schedule: Single-unit prototype orders and multi-unit project rollouts are quoted and scheduled differently — tell us which one you're placing.
Every dry type transformer Honway ships is engineered against these five inputs rather than selected off a fixed spec sheet.
FAQ
What is a dry type power transformer?
A dry type power transformer is a transformer that uses solid insulation materials and air cooling instead of liquid insulation oil.
What is the difference between dry type and oil immersed transformers?
Dry type transformers are commonly selected for indoor and fire-sensitive environments, while oil immersed transformers are widely used where liquid insulation systems are suitable.
Can dry type transformers be customized?
Yes. Transformer parameters can be evaluated according to project requirements, including capacity, voltage and structural requirements.
What information is needed before requesting a quotation?
Customers should provide electrical specifications, installation conditions and project requirements to allow accurate transformer selection.
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